<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
   <input type="text">
</body>
<script>
  const ipt=document.querySelector("input")
  let reg=/^(?!.*向军.*).{5,6}$/
  ipt.addEventListener("keyup", function () {
     console.log(reg.test(this.value));
  })
</script>
</html>